Hectograph blanket and method of preparing same



V porate these lacquer which contains a Patented 27,1945

.umreo s'mes PATENT I orrlce HECTOGRAPH BLANKET AND 'METHOD OF PREPARING SAME Robert 0. Bear, Chicago, 11L, assignor to Ditto;

Incorporated, Chicago, 111., a corporation 01' West Virginia No Drawing.

Claims.

The invention relates toa hectograph blanket and method of preparing same. More particularly the invention relates to a hectograph blanket comprising a copy mass, it fibrous backing which have hitherto been used for this purpose do not prevent the drying oil from penetrating into v the fiber of the cloth or paper backing. Thus the-full benefit oi the oil for bonding is not obtained; also the presence oi. the oil in the backing causes progressive and overtanning of a copy mass which comes in contact with the backing 1 when the hectograph blanket is in the form of a roll. i l

An object or this invention is to provide a hectograph blanket in which there is substantially no penetration of the drying oil into the lacquered backing.

Other objects and advantages of the invention willbecome apparent as the following detailed description progresses.

In accordance with this invention, the drying oil is applied to a fibrous backing which has as a final coating lacquer containing a liquid which is.

compatible with the lacquer and immiscible with the liquid drying oil.

In the preferred embodiment of the invention, I incorporate in the lacquer a small proportion of .a high boiling hygroscopic liquid containing iree methylene glycol, trlethylene glycol, 2-methyl..

2-5 pentanediol and glycol monohydroxyacetate.

The proportions ofglycols and similar materials which may be used in the lacquer may vary widely. The practical lower limits or glycol ma terials which will workin this invention range from about 3% on the solid content of the lacquer for a medium blown drying oil and is about 10%" x for a light blown drying 01!. Higher amounts, of

I course, may be used up to the limit of compatibility with the lacquer.

The glycol may be incorporated to advantagein any lacquer which dries to a water insoluble mm, but it is particularly' -advantageousto incorplasticizer which is such as linseed oil,

compatible with a drying oil 7 be used in the Wild? A y was drying il m y materials in a cellulose-ester or resin Application February 13, 1942, Serial No. 430,743

ing layer. Oneadvantageot this invention is that'it-allows the, use of thin bodied drying oils,

as well as the heavy blown oils. The thin bodied 1 drying oils such as the light and medium blown linseed oils give better bonding than the thickerdrying oils but hitherto the excessive penetration of these oils into the backing has retarded their I use. By this invention such penetration is prevented. Also by this invention it is possible to spread th drying oil on the backing in a thinner layer than has been customary. V i The following are examples of lacquers which have been found suitable in the practice of my invention:

7 Parts by weight I. Nitrocellulose .i...l 25

Glycol monohydroxyacetate 10 Butanol Butyl acetate 10 vlli'thyl acetate Toluene -L .20

' I Parts by weight IILNitrocelluiose Propylene glycol. l0 Butyl alcohol l5 Butyl' acetate l0 Ethyl acetate 20 Toluene 20 Parts by weight HI. Nitrocellulose 20' Castor oil 5. 2-methyL'2-4 pentanediol 10 Ethyl acetate ------a-'---'- 25 But-y] alcohol l0 Butyl acetate 1c Toluene- 20 The lacquers given above were used to coat and impregnate a cloth backing. After drying, a coating of linseed oil was applied to one side oi the lacquered backing and allowed todry for several hours. The copy mass composition, such as an ordinary gelatin hectograph composition, wasapplied' tothe dried linseed oil to form a hectograph blanket in the manner well known to th art. This blanket was characterized by showing substantially no penetration of the drying oil into the cloth hac, similar results were obtained with a lacquered paper hacking and with drying oil bonding agents other than linseed oil.

while there have been shown and described certain embodiments of the invention, itis to he understood thati t is capable at many modifies:

tions. Changes, therefore, may be made without departing from the spirit and scope oi the invention as described in the appended claims, in which it is the intention to claim all novelty inherent in the invention as broadly as possible, in view of th prior art.

I claim: I a

1; A hectograph blanket comprising a tannable gelatinous copy mass, a fibrous backing and an intermediate bonding layer comprising a drying oil. said fibrous backing being coated with a lacquer containing a liquid selected from the group consisting of polyhydric alcohols and incompletely esteritled polyhydric alcohols.

2. A hectograph blanket comprising a tannable gelatinous copy mass, a fibrous backing and an intermediate bonding layer comprising a drying oil, said fibrous backing being coated with a lacquer containing a polyhydric alcohol.

3. A hectograph blanket comprising atannable gelatinous copy mass, a fibrous backing and an intermediate bonding layer comprising a drying oil, said fibrous backing being coated with a lacquer containing propylene glycol.

4. A hectograph blanket comprising a tannable gelatinous copy mass a fibrous backing and an intermediate bonding layer comprising a. drying oil, said fibrous backing being coated with a lacquer containing 2-methyl, 2-4 pentanediol.

5. A hectograph blanket comprising a tannabie gelatinous copymass, a fibrous backing and an intermediate bonding layer comprising a drying oil, said fibrous backing being coated with a lacquer containing glycol monohydroxyacetate.

ROBERT C. 30173. 

